Allen-Bradley 1742-LP120A is the MAC processor module of the Bulletin 1742 Modular Automation Controller family, designed for 110/120 VAC operation in early AB automation systems. This Series A processor, produced by AB Milwaukee in the late 1970s to early 1980s, provides centralized control for modular automation configurations and accepts 110/120 VAC input at 50/60 Hz. It served as the control core for early modular automation configurations within MAC systems. Variants such as 1742-LP120A-K appear in current listings, reflecting its role as a processor module within a MAC chassis.
